Antibackflow valve



NOV. 4, 1952 CQQN 2,616,512

' ANTIBACKFLOW VALVE Filed April 6, 1950 INVENTOR EVERETT P. Coo/v ATTORNEY Patented Nov. 4, 1952 NIT-ED STATES PATENT oss-ic s 2,616,512 ANT'mAcKFLow VALVE Everett II. 60011, Boise, Idaho Application April *6, 1950, Serial No. 154,248

'1 Claim.

This invention relates to antibaokflow "valves and, more particularly, to a valvefor-preventin'g ingress of sewage or tidewat'er to a building outflow system.

The primary object of this invention is to provide an anti-backwater valve for connection between the sewage outflow pipe, generally in the basement or ground floor of the building, and the main sewage line or branch line, the particular object being to provide such a valve that will conserve the grade in the system. The problem of preventing backflow of sewage or tidal waters from a sewage outflow and related pipes in a building almost invariably occur where there is very little grade between the pipes in thebottom of a building and the main sewage line. When the main sewage line is overlooked or when the tidal or rain waters back up in the main sewer line, there results the obvious tendency for the sewage to back up into the lower parts of the building sewage system, thereby creating untenable conditions in the building but also with a resultant deposit of trash and debris in the building sewage system. Accordingly, it is now intended to provide an anti-backwater valve installable in existing systems without, material loss of grade or "change'in direction of the'existing pipes.

Another object of the invention is to provide an anti-backwater valve which, in operation, relies almost entirely on gravity and flotation, respectively, for its opening and closing. Stated conversely, it is proposed now to provide a gravity-opening, flotation-closing ball valve which does not depend in any material respect on the velocity of out-flowing sewage for its opening or, on the other hand, does not depend on velocity of backwater for its closing, the importance of this phase of the invention being appreciable in that sewage systems having backwater problems have relatively little fall and consequently relatively little velocity in the flow of sewage or water in either direction. In contrast with previous attempts to provide a substantially horizontally arranged check valve wherein velocity of flow therethrough invariably played an important part, the object now is to provide a flotation type check valve wherein only the significant opening and closing movements of the ball are in a substantially vertical direction and wherein the other movements of the ball approach the horizontal. By limiting the vertical path of movement of the ball, the vertical dimensioning of the entire valve is thereby held to the minimum.

"through the "middle of the valve; and

Fig. 2 is 'a vertical transverse section taken along the line 2-2 of Fig. 1. 7

Referring now to the drawing'ijn which like reference numerals denote similar elements, the backwater valve has ajhollow casing indicated generally at 2 and preferably cast of suitable metal such as iron. Casing 2 is generally '2- shaped and comprises a horizontal inlet pipe 4 dimensioned for fitting with a sewage pipe usually extending horizontally beneath the basement or ground floor of a building. Preferably, a slight excavation is made to accommodate casing '2 so that it're'sts in the positionshown in Fig.1 ofthe drawing. Horizontal inlet pipe 4 terminates in a cylindrical cleanout chamber 6 which is closed at its top by removable closure cap 8 preferably formed of brass, it being obvious that when cap 8 is removed, any debris collecting in chamber 6 may be removed manually or forced downwardly through the valve.

In the bottom of chamber 6 there is formed a relatively large vertical passage Ill surrounded by a flanged recess l2 in which fits an annular valve seat [4, preferably formed of neoprene or other plastic material resistant to rease and oil and including on its working face an annular ring seal Hi. In the region below valve seat I4, casing 2, on the outlet side of the valve, extends downwardly in the region indicated generally at 11, corresponding to the vertical leg or juncture member of a Z, and thence laterally to terminate in a horizontally extending outlet I8. In the interior of the angle between downwardly and laterally extending portions I1 and I8 there is an enlargement in the top of outlet l8 constituting an ante-chamber 20 having a semi-cylindrical upper wall 2| as best seen in Fig. 2. The interior of ante-chamber 2B is contiguous with the remainder of the interior of the outlet side of the valve, there being a pair of guide ribs 22 oppositely disposed on each side of the lower portion of the ante-chamber. As shown in Fig. 1 guide ribs 22 are inclined upwardly from right to left, the upper portions 22a lying immediately below valve seat l4 being relatively steeply inclined and the lower portions 22b lying below ante-chamber 20 being relatively gradually inclined. It will be observed further that the disposition and inclination of guide ribs 22 correspond with the upper semi-cylindrical wall 2| of ante-chamber 20 so as loosely to confine a hollow floating ball 26. Ball 26 may be suitably formed of sheet metal or plastic.

Ball 26 is shown in full line position in Fig. 1 seated upwardly against ring seal I6 of valve seat M, a position it assumes by floating backwardly and upwardly on backwater rising through outlet 18. In the normal operation of the valve, when there is no backwater, ball 26 rolls by gravity down steeply inclined rib portions 22a and thence laterally away on gradually inclined rib portions 22b to its dash line position. It will be observed that in the dash line position of ball 26, the latter lies almost entirely out of the line of normal flow of sewage passing through the valve. However, backwater risin in the outlet side of the valve will reach ball 26 when the latter is in its dash line position long before it rises to the level of seat It. Thus. in the latter rising movements of the backwater, ball 26 floats upwardly and laterally to its full line position wherein it seats against ring seal 16 so as to prevent any backflow through the valve.

In event a cleanout becomes necessary, closure 8 is lifted from chamber 6 whereupon large debris may be manually removed or forced downwardly passed valve II. It is noteworthy that any debris forced or washed through valve seat l4 passes on directly to outlet t8. Because of the arrangement of ante chamber 20 contiguous with and above outlet [8, and the disposition of the ribs 22 adjacent the flow path, sewage through which valve tends always to keep ante chamber 20, ribs 22 and ball 26 free of debris or encumbering deposits.

The invention described above is not limited to the structure specifically disclosed, but is in- '4 tended to cover all modifications, substitutions, and equivalents within the scope of the following claim.

I claim:

An anti-backfiow valve comprising a hollow casing having a substantially horizontally extending inlet conduit terminating in a cylindrical chamber with substantially coaxial openings through the upper and lower sides thereof and having an outlet conduit extending downwardly and thence laterally from the open lower end of said chamber, a removable cap for the opening in the upper side of said chamber, the lower side of said chamber having an upwardly facing substantially annular shoulder therein surrounding the opening and defining a pocket for receiving a valve seat, an annular valve seat engaged in said pocket, the inner periphery of said valve seat protruding inwardly into the lastnamed opening, inclined guide ribs extending longitudinally along opposite sides of said outlet conduit, said guide ribs having upper end portions lying substantially beneath said valve seat and lower end portions extending laterally therefrom towards the outlet end of said outlet conduit, and a bouyant valve rollably supported on said ribs, whereby normally said ball valve is assisted by gravity to roll on said ribs but, upon rise of backwater in said outlet conduit, floats upwardly to close against said seat.

EVERETT P. COON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 199,307 Naeher Jan. 15, 1878 486,177 Couzens Nov. 15, 1892 1,549,007 Khun Aug. 11, 1925 FOREIGN PATENTS Number Country Date 19,135 Great Britain Aug. 19, 1897 436,806 Great Britain Oct 18, 1935 

